In current tank and evaporative emission control systems on gasoline vehicles, the tightness (i.e. detecting the sealing thereof/detecting if the tank is airtight) is determined by leak detection based on two general methods. Leaks can be detected after pressurizing or applying a vacuum to the tank system. Car manufacturers currently use both techniques.
All these systems have some disadvantages. One of the most important factors which results in these disadvantages is leak detection technique complicity and sensitivity of components. In pressurized systems the components may be sensitive (i.e. not robust) to solid or liquid contamination and environmental conditions. Leak detection by applying vacuum is time consuming and difficult for application in hybrid vehicles. Current leak detection modules are very complicated and have a many close-fitting connections; this not only increases the cost of assembly but also increases the risk of failure, thus compromising the reliability.
It is an object of the invention to provide an improved system. It is a further object of the invention to provide a system and method of leak detection having improved reliability and robustness.